Summary/Abstract Youth under age 18 involved in the criminal justice system are disproportionately minorities and affected by substance abuse, mental illness, and HIV/STI. Most young offenders are released on community supervision without the STI, mental health, or substance use screening, diagnosis, and treatment afforded detained youth, despite similar rates of risk behavior. Their long-term trajectory is poor, the costs to society are high, and lasting effects on community well-being and individual employment prospects are profound. Altering this trajectory is a public health priority. Preventing HIV Among Teens (PHAT) Life is an evidence-based program that meets the need in juvenile justice to address youths' co-morbid health problems. The next??and perhaps most critical??step in ensuring that this decade-long line of research produces actual, real-world improvements in the lives of probation youth is to develop a PHAT Life training strategy that is effective, cost-effective, and sustainable within juvenile justice settings. This private/public collaboration between Oregon Research Behavioral Intervention Strategies and the University of Illinois at Chicago will leverage existing resources and competencies to create a commercially viable technology-based training tool for PHAT Life with great potential for sustainability and cost-effectiveness. Building on PHAT Life's past research, in this SBIR Phase I research we will (a) develop and evaluate a prototype interactive web browser and mobile app multimedia training tool to enable para-professionals (e.g., health educators, probation staff, youth care staff) to deliver PHAT Life to youth on probation, and (b) identify additional training materials needed to address facilitator gaps (e.g., HIV/STI knowledge, managing group dynamics). The proposed technology-based training tool should be highly sustainable, because it (a) relies on ?indigenous? personnel to deliver the intervention, (b) is likely to prove cost-effective since we will utilize a technology that can deliver training at scale, and (c) will improve fidelity both by leveraging technology to provide consistent training experiences to para-professionals and by including a computer-mediated video recorded observation of group sessions that will be reviewed and graded by an expert trainer to increase the likelihood of intervention implementation fidelity.